Tom Marlow prepares kegs of cold-brewed coffee infused with nitrogen at Portland’s Fork Food Lab. The brew is smoother and creamier than other coffees, fans say, and the cold water extracts more of the beans’ sweet flavors.

Dave Mallari wasn’t too sure at first about adding nitrogen-infused coffee to the menu at The Sinful Kitchen, his small brunch restaurant on Brighton Avenue.

He started by ordering just one 5-gallon keg a week of the specialty coffee, which is infused with nitrogen gas and served chilled on tap, like beer – sometimes straight up, sometimes with added ice. Now, eight months later, he can go through four kegs a week. He’s also stocking to-go cups to serve the customers who have gotten hooked on the brew and pop in first thing in the morning.

The Arabica Coffee shop on Free Street has been selling nitro coffee for just two to three months, and already sales of the drink account for an estimated 15 to 20 percent of the shop’s total sales of iced coffees. Demand is so great that the shop often runs out.

“For something that’s brand new for us and we haven’t put a lot of leg work into advertising it, that’s fantastic,” said Andy McClure, the shop’s manager.

It wasn’t that long ago that cold brew coffee became the new, hip drink in coffee bars all around the country. Now that cold brew is mainstream (you can get it at Dunkin’ Donuts) a subset of that category, nitro coffee, is fast becoming the new favorite among coffee drinkers who like specialty brews and trying something new – and who don’t mind paying $4 or more per 16-ounce cup.

SMOOTHER, CREAMIER, SWEETER

It’s still too early to predict whether nitro coffee taps will eventually make their way into every corner store, but the National Coffee Association is impressed with the drink’s performance so far. This year, for the first time, nitro was included in the association’s 2017 National Coffee Drinking Trends Report. The report found that 3 percent of those surveyed who drank coffee in the previous week had downed a cup of nitro. That doesn’t sound like much, but the NCA called it “a strong debut.” (Regular cold brew clocked in at 11 percent.)

Portland has become a haven for nitro coffee lovers, helped by startup brewer White Cap and Exeter, N.H., wholesaler Nobl Coffee. The brew is said to be sweeter than other coffees and, with its thin layer of foam, resembles a dark beer.

What’s the appeal of nitro coffee? With its rich, dark color and thin layer of crema, or foam, that forms on top, nitro invites comparisons to Guinness beer. Fans say the taste and texture are smoother and creamier than other coffees, and it’s a little sweeter, too. Most people find no need to add cream or sugar to a nitro coffee.

“It’s so smooth, and you can actually taste the nuances of the coffee, the chocolatey caramel undertones,” said Jill Dutton, co-owner of The Cheese Iron in Scarborough, which sells Rwandan Reserve and Namaste Chai nitro coffees from White Cap Coffee, a start-up nitro brewer working out of Fork Food Lab in Portland.

The Cheese Iron started selling nitro in May and is already going through two kegs a week; sales have eclipsed the shop’s hot coffee.

The brewing process, whose origins are unclear, creates the drink’s more subtle but satisfying flavors.

“Since you’re not putting hot water over grounds, you’re not changing the chemical nature of the oils in the coffee,” said Tom Marlow, co-owner of White Cap. “The cold water has a higher propensity to extract the more sweet flavors from the coffee beans and less of the bitter, astringent type of flavors that you might associate with a cooled down cup of hot coffee that’s been sitting on the desk a little too long.”

White Cap brews with beans roasted by another Portland startup, the Rwanda Bean Coffee.

PORTLAND EMBRACES THE TREND

In Portland, the market for nitro is going nuts, thanks largely to White Cap and Nobl Coffee, a wholesaler based in Exeter, New Hampshire. The two brewers are selling their nitro to local businesses as varied as Bayside Bowl, the Portland Food Co-op, Otherside Delicatessen, Ri Ra and, of course, coffee shops such as Arabica and Coffee By Design. Many of these spots are selling growlers of nitro as well.

“When it’s a hot day, we have to order more because it will totally sell out,” said Mary Alice Scott, community engagement manager at the Portland Food Co-op, where a Columbian brew and a Madagascar vanilla bean coffee are on tap.

White Cap’s Marlow, who is an engineer with a law degree, and his partner Ben Graffius, a merchant marine captain, launched their business last September out of Fork Food Lab. They’re now servicing nine locations in southern Maine and plan to create a larger brewery and tasting room on the Portland peninsula later this fall. Marlow said the new nitro brewery will be “modeled around a brewery, but it’s in essence a different kind of coffee shop.”

“We’ll have multiple flavors of the nitro brew,” he said. “We’ll also have hot coffee available because some people just like to have hot coffee. But from a nitro perspective, we’ll be doing tasting flights so you could get a few (coffees) of different origins and have some basic food to pair with that. Basically what we want to do is take that experience that you get at a brewery tasting room and do it similarly for coffee.”

Nobl Coffee was founded two and a half years ago and distributes nitro coffee throughout New England. The company has been pushing hard into Maine, says owner Connor Roelke, because Portland has “one of the hippest food scenes in the area. It’s right behind Boston.”

Tom and Lindsay Marlow agitate a keg of cold-brewed White Cap Coffee at Fork Food Lab. The brewing process makes for a more nuanced flavor. “Since you’re not putting hot water over grounds, you’re not changing the chemical nature of the oils in the coffee,” Tom Marlow says. White Cap uses beans roasted by another Portland startup, Rwanda Bean Coffee.

Roelke had fewer than 10 Maine accounts last year; over the past year his Maine business has ballooned to 30-plus accounts.

Roelke uses beans from a dozen different New England coffee roasters, including Portland’s Coffee By Design. He has also installed nitro taps in all of the Coffee By Design cafes. Alan Spear, co-owner of Coffee By Design, says sales of nitro coffee have “just exploded” for his company.

The Coffee By Design in Freeport, for example, goes through 40 kegs of cold brew in a busy weekend, he said, and half of that is nitro cold brew.

While most people enjoy nitro on its own, one advantage of the brew is it can be used in more creative ways than traditional iced coffee. The staff at The Sinful Kitchen is using nitro to make specialty cocktails, such as a boozy mochaccino and an espresso martini that’s made with nitro cold brew, Baileys Irish Cream and vanilla vodka, garnished with espresso beans.

BREW A WAY TO LURE CUSTOMERS

At LB Kitchen on Congress Street, which has been serving nitro for two months, the coffee is going into “wellness mocktails,” such as the hibiscus cold brew sparkler, which is made with homemade hibiscus syrup, nitro coffee and sparkling water. Co-owner Bryna Gootkind says she plans to release similar new drinks one at a time. Next up: a coffee-based lemonade.

“Pairing coffee with citrus totally changes the profile of both coffee and citrus,” Gootkind said. “It becomes something that is delicious and sort of familiar because you’ve had them both, but something happens with the two of them together.”

You can still get a cup of “plain” nitro coffee there, too, for $3.50 per 16-ounce cup, a relative bargain.

Nitro coffee costs more because of the complex brewing process, which requires a much higher coffee-to-water ratio, Spear says. Cold brews can take anywhere from 12 to 24 hours (at Coffee By Design, it’s 24 hours) to prepare, and need five pounds of coffee to make just five gallons.

Nitro coffee is good not only for coffee shops’ immediate bottom lines, but for their long-term health. At a time when consumers can buy coffee anywhere, including in cans in the grocery’s refrigerated aisle, specialty coffees like nitro help lure customers back to the comfy couches of local coffee shops.

“It’s very easy for people to make quality coffee at home now,” said McClure, the manager at Arabica. “You can go anywhere and find coffee. Portland is a particularly saturated town as far as coffee shops, too. Doing something like this gives you an edge.”

Meredith Goad can be contacted at 791-6332 or at:

mgoad@pressherald.com

Twitter: MeredithGoad